Kim Sengupta: What now for mission built to McChrystal's orders?

The Rolling Stone article that led to the fall of General Stanley McChrystal was being described last night as the "longest suicide note in history". The question now is just how much damage it will do to the military campaign in Afghanistan which was designed and honed very much to the specification of the departed US commander.

The choice of David Petraeus to replace General McChrystal was a surprise but it may prove to be an inspired choice.

Although it became clear yesterday that General McChrystal would not survive he still appeared to retain the support of American and allied commanders in the war. While his fate was being decided in Washington, British, Canadian and French senior officers warned that removing him at such a crucial stage of the Afghan conflict would be damaging.

Slotting in General Petraeus sends the signal that President Obama remains fully committed to the Afghan mission. There will also be a degree of continuity, General Petraeus's job as head of US Central Command meant that he was in overall charge of the Afghan and Iraqi operations and familiar with the challenges. Furthermore, General McChrystal had worked for General Petraeus in Baghdad on the "surge" on which the current Afghan "surge" is loosely based.

The feeling of betrayal apparently felt by General McChrystal and his aides is now public knowledge thanks to the Rolling Stone article. But it was no surprise to those who had followed the twists and turns of the Afghan war. The fiercely loyal followers of the General were vociferous in their criticism of those within the US administration who attempted to block his vision of how the tide of insurgency could be turned.

This remained largely unreported because most of the comments were off the record and because there was a feeling among journalists that General McChrystal's openness should not result in every racy comment appearing in print.

Vice-President Joe Biden, who had opposed General McChrystal's request for tens of thousands of reinforcements, was described by McChrystal supporters as "the Donald Rumsfeld of Afghanistan". It was an allusion to the disastrous refusal of George Bush's vice-president to send adequate forces to Iraq after the fall of Saddam Hussein, one of the main reasons for the country sliding into a state of semi-anarchy.

The tensions sometimes did become public – such as General McChrystal's remarks on the fringes of a Nato meeting that the Biden plan would create a lawless "Chaostan".

There was little attempt to hide the anger in the McChrystal camp when it emerged that while the military commander was pressing for extra troops, his civilian counterpart, Karl Eikenberry, the US ambassador, had been sending secret memorandums to the White House arguing against that move. A group of journalists, including myself, were invited to the headquarters of Isaf ( International Security Assistance Force) in Kabul to be told by a senior officer: "He ambushed us... the guy went behind our backs."

Mr Eikenberry, a former military officer himself, had been dismayed by the way the previous US commander in Afghanistan, General David McKiernan, had been pushed aside to make way for General McChrystal. Mr Eikenberry, among others, felt that General McKiernan had done nothing to deserve the indignity of becoming the first US commander to be relieved of his post since Douglas MacArthur in the Korean War. Yesterday, he, Mr Biden and General McKiernan may well have felt a sense of schadenfreude. Where the sacking leaves the Afghan mission is a different matter, with General McChrystal now the third US commander to be fired during this war.